packages/flutter/lib/src/material/outline_button.dart - mirrors/flutter - Git at Google

 // Copyright 2018 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 import 'package:flutter/foundation.dart';
 import 'package:flutter/widgets.dart';

 import 'button_theme.dart';
 import 'colors.dart';
 import 'material_button.dart';
 import 'raised_button.dart';
 import 'theme.dart';

 // The total time to make the button's fill color opaque and change
 // its elevation. Only applies when highlightElevation > 0.0.
 const Duration _kPressDuration = Duration(milliseconds: 150);

 // Half of _kPressDuration: just the time to change the button's
 // elevation. Only applies when highlightElevation > 0.0.
 const Duration _kElevationDuration = Duration(milliseconds: 75);

 /// Similar to a [FlatButton] with a thin grey rounded rectangle border.
 ///
 /// The outline button's border shape is defined by [shape]
 /// and its appearance is defined by [borderSide], [disabledBorderColor],
 /// and [highlightedBorderColor]. By default the border is a one pixel
 /// wide grey rounded rectangle that does not change when the button is
 /// pressed or disabled. By default the button's background is transparent.
 ///
 /// If the [onPressed] callback is null, then the button will be disabled and by
 /// default will resemble a flat button in the [disabledColor].
 ///
 /// The button's [highlightElevation], which defines the size of the
 /// drop shadow when the button is pressed, is 0.0 (no shadow) by default.
 /// If [highlightElevation] is given a value greater than 0.0 then the button
 /// becomes a cross between [RaisedButton] and [FlatButton]: a bordered
 /// button whose elevation increases and whose background becomes opaque
 /// when the button is pressed.
 ///
 /// If you want an ink-splash effect for taps, but don't want to use a button,
 /// consider using [InkWell] directly.
 ///
 /// Outline buttons have a minimum size of 88.0 by 36.0 which can be overridden
 /// with [ButtonTheme].
 ///
 /// See also:
 ///
 ///  * [RaisedButton], a filled material design button with a shadow.
 ///  * [FlatButton], a material design button without a shadow.
 ///  * [DropdownButton], a button that shows options to select from.
 ///  * [FloatingActionButton], the round button in material applications.
 ///  * [IconButton], to create buttons that just contain icons.
 ///  * [InkWell], which implements the ink splash part of a flat button.
 ///  * <https://material.io/design/components/buttons.html>
 class OutlineButton extends MaterialButton {
   /// Create an outline button.
   ///
   /// The [highlightElevation] argument must be null or a positive value
   /// and the [clipBehavior] argument must not be null.
   const OutlineButton({
     Key key,
     @required VoidCallback onPressed,
     ButtonTextTheme textTheme,
     Color textColor,
     Color disabledTextColor,
     Color color,
     Color highlightColor,
     Color splashColor,
     double highlightElevation,
     this.borderSide,
     this.disabledBorderColor,
     this.highlightedBorderColor,
     EdgeInsetsGeometry padding,
     ShapeBorder shape,
     Clip clipBehavior = Clip.none,
     Widget child,
   }) : assert(highlightElevation == null || highlightElevation >= 0.0),
        super(
          key: key,
          onPressed: onPressed,
          textTheme: textTheme,
          textColor: textColor,
          disabledTextColor: disabledTextColor,
          color: color,
          highlightColor: highlightColor,
          splashColor: splashColor,
          highlightElevation: highlightElevation,
          padding: padding,
          shape: shape,
          clipBehavior: clipBehavior,
          child: child,
        );

   /// Create an outline button from a pair of widgets that serve as the button's
   /// [icon] and [label].
   ///
   /// The icon and label are arranged in a row and padded by 12 logical pixels
   /// at the start, and 16 at the end, with an 8 pixel gap in between.
   ///
   /// The [highlightElevation] argument must be null or a positive value. The
   /// [icon], [label], and [clipBehavior] arguments must not be null.
   factory OutlineButton.icon({
     Key key,
     @required VoidCallback onPressed,
     ButtonTextTheme textTheme,
     Color textColor,
     Color disabledTextColor,
     Color color,
     Color highlightColor,
     Color splashColor,
     double highlightElevation,
     Color highlightedBorderColor,
     Color disabledBorderColor,
     BorderSide borderSide,
     EdgeInsetsGeometry padding,
     ShapeBorder shape,
     Clip clipBehavior,
     @required Widget icon,
     @required Widget label,
   }) = _OutlineButtonWithIcon;

   /// The outline border's color when the button is [enabled] and pressed.
   ///
   /// By default the border's color does not change when the button
   /// is pressed.
   final Color highlightedBorderColor;

   /// The outline border's color when the button is not [enabled].
   ///
   /// By default the outline border's color does not change when the
   /// button is disabled.
   final Color disabledBorderColor;

   /// Defines the color of the border when the button is enabled but not
   /// pressed, and the border outline's width and style in general.
   ///
   /// If the border side's [BorderSide.style] is [BorderStyle.none], then
   /// an outline is not drawn.
   ///
   /// If null the default border's style is [BorderStyle.solid], its
   /// [BorderSide.width] is 1.0, and its color is a light shade of grey.
   final BorderSide borderSide;

   @override
   Widget build(BuildContext context) {
     final ButtonThemeData buttonTheme = ButtonTheme.of(context);
     return _OutlineButton(
       onPressed: onPressed,
       brightness: buttonTheme.getBrightness(this),
       textTheme: textTheme,
       textColor: buttonTheme.getTextColor(this),
       disabledTextColor: buttonTheme.getDisabledTextColor(this),
       color: color,
       highlightColor: buttonTheme.getHighlightColor(this),
       splashColor: buttonTheme.getSplashColor(this),
       highlightElevation: buttonTheme.getHighlightElevation(this),
       borderSide: borderSide,
       disabledBorderColor: disabledBorderColor,
       highlightedBorderColor: highlightedBorderColor ?? buttonTheme.colorScheme.primary,
       padding: buttonTheme.getPadding(this),
       shape: buttonTheme.getShape(this),
       clipBehavior: clipBehavior,
       child: child,
     );
   }

   @override
   void debugFillProperties(DiagnosticPropertiesBuilder properties) {
     super.debugFillProperties(properties);
     properties.add(ObjectFlagProperty<VoidCallback>('onPressed', onPressed, ifNull: 'disabled'));
     properties.add(DiagnosticsProperty<ButtonTextTheme>('textTheme', textTheme, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('textColor', textColor, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('disabledTextColor', disabledTextColor, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('highlightColor', highlightColor, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('splashColor', splashColor, defaultValue: null));
     properties.add(DiagnosticsProperty<double>('highlightElevation', highlightElevation, defaultValue: null));
     properties.add(DiagnosticsProperty<BorderSide>('borderSide', borderSide, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('disabledBorderColor', disabledBorderColor, defaultValue: null));
     properties.add(DiagnosticsProperty<Color>('highlightedBorderColor', highlightedBorderColor, defaultValue: null));
     properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('padding', padding, defaultValue: null));
     properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));
   }
 }

 // The type of of OutlineButtons created with OutlineButton.icon.
 //
 // This class only exists to give OutlineButtons created with OutlineButton.icon
 // a distinct class for the sake of ButtonTheme. It can not be instantiated.
 class _OutlineButtonWithIcon extends OutlineButton with MaterialButtonWithIconMixin {
   _OutlineButtonWithIcon({
     Key key,
     @required VoidCallback onPressed,
     ButtonTextTheme textTheme,
     Color textColor,
     Color disabledTextColor,
     Color color,
     Color highlightColor,
     Color splashColor,
     double highlightElevation,
     Color highlightedBorderColor,
     Color disabledBorderColor,
     BorderSide borderSide,
     EdgeInsetsGeometry padding,
     ShapeBorder shape,
     Clip clipBehavior,
     @required Widget icon,
     @required Widget label,
   }) : assert(highlightElevation == null || highlightElevation >= 0.0),
        assert(icon != null),
        assert(label != null),
        super(
          key: key,
          onPressed: onPressed,
          textTheme: textTheme,
          textColor: textColor,
          disabledTextColor: disabledTextColor,
          color: color,
          highlightColor: highlightColor,
          splashColor: splashColor,
          highlightElevation: highlightElevation,
          disabledBorderColor: disabledBorderColor,
          highlightedBorderColor: highlightedBorderColor,
          borderSide: borderSide,
          padding: padding,
          shape: shape,
          clipBehavior: clipBehavior,
          child: Row(
            mainAxisSize: MainAxisSize.min,
            children: <Widget>[
              icon,
              const SizedBox(width: 8.0),
              label,
            ],
          ),
        );
 }

 class _OutlineButton extends StatefulWidget {
   const _OutlineButton({
     Key key,
     @required this.onPressed,
     this.brightness,
     this.textTheme,
     this.textColor,
     this.disabledTextColor,
     this.color,
     this.highlightColor,
     this.splashColor,
     @required this.highlightElevation,
     this.borderSide,
     this.disabledBorderColor,
     @required this.highlightedBorderColor,
     this.padding,
     this.shape,
     this.clipBehavior,
     this.child,
   }) : assert(highlightElevation != null && highlightElevation >= 0.0),
        assert(highlightedBorderColor != null),
        super(key: key);

   final VoidCallback onPressed;
   final Brightness brightness;
   final ButtonTextTheme textTheme;
   final Color textColor;
   final Color disabledTextColor;
   final Color color;
   final Color splashColor;
   final Color highlightColor;
   final double highlightElevation;
   final BorderSide borderSide;
   final Color disabledBorderColor;
   final Color highlightedBorderColor;
   final EdgeInsetsGeometry padding;
   final ShapeBorder shape;
   final Clip clipBehavior;
   final Widget child;

   bool get enabled => onPressed != null;

   @override
   _OutlineButtonState createState() => _OutlineButtonState();
 }


 class _OutlineButtonState extends State<_OutlineButton> with SingleTickerProviderStateMixin {
   AnimationController _controller;
   Animation<double> _fillAnimation;
   Animation<double> _elevationAnimation;
   bool _pressed = false;

   @override
   void initState() {
     super.initState();

     // When highlightElevation > 0.0, the Material widget animates its
     // shape (which includes the outline border) and elevation over
     // _kElevationDuration. When pressed, the button makes its fill
     // color opaque white first, and then sets its
     // highlightElevation. We can't change the elevation while the
     // button's fill is translucent, because the shadow fills the
     // interior of the button.

     _controller = AnimationController(
       duration: _kPressDuration,
       vsync: this,
     );
     _fillAnimation = CurvedAnimation(
       parent: _controller,
       curve: const Interval(0.0, 0.5,
         curve: Curves.fastOutSlowIn,
       ),
     );
     _elevationAnimation = CurvedAnimation(
       parent: _controller,
       curve: const Interval(0.5, 0.5),
       reverseCurve: const Interval(1.0, 1.0),
     );
   }

   @override
   void didUpdateWidget(_OutlineButton oldWidget) {
     super.didUpdateWidget(oldWidget);
     if (_pressed && !widget.enabled) {
       _pressed = false;
       _controller.reverse();
     }
   }

   void _handleHighlightChanged(bool value) {
     if (_pressed == value)
       return;
     setState(() {
       _pressed = value;
       if (value)
         _controller.forward();
       else
         _controller.reverse();
     });
   }

   @override
   void dispose() {
     _controller.dispose();
     super.dispose();
   }

   Color _getFillColor() {
     if (widget.highlightElevation == null || widget.highlightElevation == 0.0)
       return Colors.transparent;
     final Color color = widget.color ?? Theme.of(context).canvasColor;
     final Tween<Color> colorTween = ColorTween(
       begin: color.withAlpha(0x00),
       end: color.withAlpha(0xFF),
     );
     return colorTween.evaluate(_fillAnimation);
   }

   BorderSide _getOutline() {
     if (widget.borderSide?.style == BorderStyle.none)
       return widget.borderSide;

     final Color specifiedColor = widget.enabled
       ? (_pressed ? widget.highlightedBorderColor : null) ?? widget.borderSide?.color
       : widget.disabledBorderColor;

     final Color themeColor = Theme.of(context).colorScheme.onSurface.withOpacity(0.12);

     return BorderSide(
       color: specifiedColor ?? themeColor,
       width: widget.borderSide?.width ?? 1.0,
     );
   }

   double _getHighlightElevation() {
     if (widget.highlightElevation == null || widget.highlightElevation == 0.0)
       return 0.0;
     return Tween<double>(
       begin: 0.0,
       end: widget.highlightElevation,
     ).evaluate(_elevationAnimation);
   }

   @override
   Widget build(BuildContext context) {
     return AnimatedBuilder(
       animation: _controller,
       builder: (BuildContext context, Widget child) {
         return RaisedButton(
           textColor: widget.textColor,
           disabledTextColor: widget.disabledTextColor,
           color: _getFillColor(),
           splashColor: widget.splashColor,
           highlightColor: widget.highlightColor,
           disabledColor: Colors.transparent,
           onPressed: widget.onPressed,
           elevation: 0.0,
           disabledElevation: 0.0,
           highlightElevation: _getHighlightElevation(),
           onHighlightChanged: _handleHighlightChanged,
           padding: widget.padding,
           shape: _OutlineBorder(
             shape: widget.shape,
             side: _getOutline(),
           ),
           clipBehavior: widget.clipBehavior,
           animationDuration: _kElevationDuration,
           child: widget.child,
         );
       },
     );
   }
 }

 // Render the button's outline border using using the OutlineButton's
 // border parameters and the button or buttonTheme's shape.
 class _OutlineBorder extends ShapeBorder {
   const _OutlineBorder({
     @required this.shape,
     @required this.side,
   }) : assert(shape != null),
        assert(side != null);

   final ShapeBorder shape;
   final BorderSide side;

   @override
   EdgeInsetsGeometry get dimensions {
     return EdgeInsets.all(side.width);
   }

   @override
   ShapeBorder scale(double t) {
     return _OutlineBorder(
       shape: shape.scale(t),
       side: side.scale(t),
     );
   }

   @override
   ShapeBorder lerpFrom(ShapeBorder a, double t) {
     assert(t != null);
     if (a is _OutlineBorder) {
       return _OutlineBorder(
         side: BorderSide.lerp(a.side, side, t),
         shape: ShapeBorder.lerp(a.shape, shape, t),
       );
     }
     return super.lerpFrom(a, t);
   }

   @override
   ShapeBorder lerpTo(ShapeBorder b, double t) {
     assert(t != null);
     if (b is _OutlineBorder) {
       return _OutlineBorder(
         side: BorderSide.lerp(side, b.side, t),
         shape: ShapeBorder.lerp(shape, b.shape, t),
       );
     }
     return super.lerpTo(b, t);
   }

   @override
   Path getInnerPath(Rect rect, { TextDirection textDirection }) {
     return shape.getInnerPath(rect.deflate(side.width), textDirection: textDirection);
   }

   @override
   Path getOuterPath(Rect rect, { TextDirection textDirection }) {
     return shape.getOuterPath(rect, textDirection: textDirection);
   }

   @override
   void paint(Canvas canvas, Rect rect, { TextDirection textDirection }) {
     switch (side.style) {
       case BorderStyle.none:
         break;
       case BorderStyle.solid:
         canvas.drawPath(shape.getOuterPath(rect, textDirection: textDirection), side.toPaint());
     }
   }

   @override
   bool operator ==(dynamic other) {
     if (identical(this, other))
       return true;
     if (runtimeType != other.runtimeType)
       return false;
     final _OutlineBorder typedOther = other;
     return side == typedOther.side && shape == typedOther.shape;
   }

   @override
   int get hashCode => hashValues(side, shape);
 }
	// Copyright 2018 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	import 'package:flutter/foundation.dart';
	import 'package:flutter/widgets.dart';

	import 'button_theme.dart';
	import 'colors.dart';
	import 'material_button.dart';
	import 'raised_button.dart';
	import 'theme.dart';

	// The total time to make the button's fill color opaque and change
	// its elevation. Only applies when highlightElevation > 0.0.
	const Duration _kPressDuration = Duration(milliseconds: 150);

	// Half of _kPressDuration: just the time to change the button's
	// elevation. Only applies when highlightElevation > 0.0.
	const Duration _kElevationDuration = Duration(milliseconds: 75);

	/// Similar to a [FlatButton] with a thin grey rounded rectangle border.
	///
	/// The outline button's border shape is defined by [shape]
	/// and its appearance is defined by [borderSide], [disabledBorderColor],
	/// and [highlightedBorderColor]. By default the border is a one pixel
	/// wide grey rounded rectangle that does not change when the button is
	/// pressed or disabled. By default the button's background is transparent.
	///
	/// If the [onPressed] callback is null, then the button will be disabled and by
	/// default will resemble a flat button in the [disabledColor].
	///
	/// The button's [highlightElevation], which defines the size of the
	/// drop shadow when the button is pressed, is 0.0 (no shadow) by default.
	/// If [highlightElevation] is given a value greater than 0.0 then the button
	/// becomes a cross between [RaisedButton] and [FlatButton]: a bordered
	/// button whose elevation increases and whose background becomes opaque
	/// when the button is pressed.
	///
	/// If you want an ink-splash effect for taps, but don't want to use a button,
	/// consider using [InkWell] directly.
	///
	/// Outline buttons have a minimum size of 88.0 by 36.0 which can be overridden
	/// with [ButtonTheme].
	///
	/// See also:
	///
	/// * [RaisedButton], a filled material design button with a shadow.
	/// * [FlatButton], a material design button without a shadow.
	/// * [DropdownButton], a button that shows options to select from.
	/// * [FloatingActionButton], the round button in material applications.
	/// * [IconButton], to create buttons that just contain icons.
	/// * [InkWell], which implements the ink splash part of a flat button.
	/// * <https://material.io/design/components/buttons.html>
	class OutlineButton extends MaterialButton {
	/// Create an outline button.
	///
	/// The [highlightElevation] argument must be null or a positive value
	/// and the [clipBehavior] argument must not be null.
	const OutlineButton({
	Key key,
	@required VoidCallback onPressed,
	ButtonTextTheme textTheme,
	Color textColor,
	Color disabledTextColor,
	Color color,
	Color highlightColor,
	Color splashColor,
	double highlightElevation,
	this.borderSide,
	this.disabledBorderColor,
	this.highlightedBorderColor,
	EdgeInsetsGeometry padding,
	ShapeBorder shape,
	Clip clipBehavior = Clip.none,
	Widget child,
	}) : assert(highlightElevation == null \|\| highlightElevation >= 0.0),
	super(
	key: key,
	onPressed: onPressed,
	textTheme: textTheme,
	textColor: textColor,
	disabledTextColor: disabledTextColor,
	color: color,
	highlightColor: highlightColor,
	splashColor: splashColor,
	highlightElevation: highlightElevation,
	padding: padding,
	shape: shape,
	clipBehavior: clipBehavior,
	child: child,
	);

	/// Create an outline button from a pair of widgets that serve as the button's
	/// [icon] and [label].
	///
	/// The icon and label are arranged in a row and padded by 12 logical pixels
	/// at the start, and 16 at the end, with an 8 pixel gap in between.
	///
	/// The [highlightElevation] argument must be null or a positive value. The
	/// [icon], [label], and [clipBehavior] arguments must not be null.
	factory OutlineButton.icon({
	Key key,
	@required VoidCallback onPressed,
	ButtonTextTheme textTheme,
	Color textColor,
	Color disabledTextColor,
	Color color,
	Color highlightColor,
	Color splashColor,
	double highlightElevation,
	Color highlightedBorderColor,
	Color disabledBorderColor,
	BorderSide borderSide,
	EdgeInsetsGeometry padding,
	ShapeBorder shape,
	Clip clipBehavior,
	@required Widget icon,
	@required Widget label,
	}) = _OutlineButtonWithIcon;

	/// The outline border's color when the button is [enabled] and pressed.
	///
	/// By default the border's color does not change when the button
	/// is pressed.
	final Color highlightedBorderColor;

	/// The outline border's color when the button is not [enabled].
	///
	/// By default the outline border's color does not change when the
	/// button is disabled.
	final Color disabledBorderColor;

	/// Defines the color of the border when the button is enabled but not
	/// pressed, and the border outline's width and style in general.
	///
	/// If the border side's [BorderSide.style] is [BorderStyle.none], then
	/// an outline is not drawn.
	///
	/// If null the default border's style is [BorderStyle.solid], its
	/// [BorderSide.width] is 1.0, and its color is a light shade of grey.
	final BorderSide borderSide;

	@override
	Widget build(BuildContext context) {
	final ButtonThemeData buttonTheme = ButtonTheme.of(context);
	return _OutlineButton(
	onPressed: onPressed,
	brightness: buttonTheme.getBrightness(this),
	textTheme: textTheme,
	textColor: buttonTheme.getTextColor(this),
	disabledTextColor: buttonTheme.getDisabledTextColor(this),
	color: color,
	highlightColor: buttonTheme.getHighlightColor(this),
	splashColor: buttonTheme.getSplashColor(this),
	highlightElevation: buttonTheme.getHighlightElevation(this),
	borderSide: borderSide,
	disabledBorderColor: disabledBorderColor,
	highlightedBorderColor: highlightedBorderColor ?? buttonTheme.colorScheme.primary,
	padding: buttonTheme.getPadding(this),
	shape: buttonTheme.getShape(this),
	clipBehavior: clipBehavior,
	child: child,
	);
	}

	@override
	void debugFillProperties(DiagnosticPropertiesBuilder properties) {
	super.debugFillProperties(properties);
	properties.add(ObjectFlagProperty<VoidCallback>('onPressed', onPressed, ifNull: 'disabled'));
	properties.add(DiagnosticsProperty<ButtonTextTheme>('textTheme', textTheme, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('textColor', textColor, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('disabledTextColor', disabledTextColor, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('color', color, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('highlightColor', highlightColor, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('splashColor', splashColor, defaultValue: null));
	properties.add(DiagnosticsProperty<double>('highlightElevation', highlightElevation, defaultValue: null));
	properties.add(DiagnosticsProperty<BorderSide>('borderSide', borderSide, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('disabledBorderColor', disabledBorderColor, defaultValue: null));
	properties.add(DiagnosticsProperty<Color>('highlightedBorderColor', highlightedBorderColor, defaultValue: null));
	properties.add(DiagnosticsProperty<EdgeInsetsGeometry>('padding', padding, defaultValue: null));
	properties.add(DiagnosticsProperty<ShapeBorder>('shape', shape, defaultValue: null));
	}
	}

	// The type of of OutlineButtons created with OutlineButton.icon.
	//
	// This class only exists to give OutlineButtons created with OutlineButton.icon
	// a distinct class for the sake of ButtonTheme. It can not be instantiated.
	class _OutlineButtonWithIcon extends OutlineButton with MaterialButtonWithIconMixin {
	_OutlineButtonWithIcon({
	Key key,
	@required VoidCallback onPressed,
	ButtonTextTheme textTheme,
	Color textColor,
	Color disabledTextColor,
	Color color,
	Color highlightColor,
	Color splashColor,
	double highlightElevation,
	Color highlightedBorderColor,
	Color disabledBorderColor,
	BorderSide borderSide,
	EdgeInsetsGeometry padding,
	ShapeBorder shape,
	Clip clipBehavior,
	@required Widget icon,
	@required Widget label,
	}) : assert(highlightElevation == null \|\| highlightElevation >= 0.0),
	assert(icon != null),
	assert(label != null),
	super(
	key: key,
	onPressed: onPressed,
	textTheme: textTheme,
	textColor: textColor,
	disabledTextColor: disabledTextColor,
	color: color,
	highlightColor: highlightColor,
	splashColor: splashColor,
	highlightElevation: highlightElevation,
	disabledBorderColor: disabledBorderColor,
	highlightedBorderColor: highlightedBorderColor,
	borderSide: borderSide,
	padding: padding,
	shape: shape,
	clipBehavior: clipBehavior,
	child: Row(
	mainAxisSize: MainAxisSize.min,
	children: <Widget>[
	icon,
	const SizedBox(width: 8.0),
	label,
	],
	),
	);
	}

	class _OutlineButton extends StatefulWidget {
	const _OutlineButton({
	Key key,
	@required this.onPressed,
	this.brightness,
	this.textTheme,
	this.textColor,
	this.disabledTextColor,
	this.color,
	this.highlightColor,
	this.splashColor,
	@required this.highlightElevation,
	this.borderSide,
	this.disabledBorderColor,
	@required this.highlightedBorderColor,
	this.padding,
	this.shape,
	this.clipBehavior,
	this.child,
	}) : assert(highlightElevation != null && highlightElevation >= 0.0),
	assert(highlightedBorderColor != null),
	super(key: key);

	final VoidCallback onPressed;
	final Brightness brightness;
	final ButtonTextTheme textTheme;
	final Color textColor;
	final Color disabledTextColor;
	final Color color;
	final Color splashColor;
	final Color highlightColor;
	final double highlightElevation;
	final BorderSide borderSide;
	final Color disabledBorderColor;
	final Color highlightedBorderColor;
	final EdgeInsetsGeometry padding;
	final ShapeBorder shape;
	final Clip clipBehavior;
	final Widget child;

	bool get enabled => onPressed != null;

	@override
	_OutlineButtonState createState() => _OutlineButtonState();
	}


	class _OutlineButtonState extends State<_OutlineButton> with SingleTickerProviderStateMixin {
	AnimationController _controller;
	Animation<double> _fillAnimation;
	Animation<double> _elevationAnimation;
	bool _pressed = false;

	@override
	void initState() {
	super.initState();

	// When highlightElevation > 0.0, the Material widget animates its
	// shape (which includes the outline border) and elevation over
	// _kElevationDuration. When pressed, the button makes its fill
	// color opaque white first, and then sets its
	// highlightElevation. We can't change the elevation while the
	// button's fill is translucent, because the shadow fills the
	// interior of the button.

	_controller = AnimationController(
	duration: _kPressDuration,
	vsync: this,
	);
	_fillAnimation = CurvedAnimation(
	parent: _controller,
	curve: const Interval(0.0, 0.5,
	curve: Curves.fastOutSlowIn,
	),
	);
	_elevationAnimation = CurvedAnimation(
	parent: _controller,
	curve: const Interval(0.5, 0.5),
	reverseCurve: const Interval(1.0, 1.0),
	);
	}

	@override
	void didUpdateWidget(_OutlineButton oldWidget) {
	super.didUpdateWidget(oldWidget);
	if (_pressed && !widget.enabled) {
	_pressed = false;
	_controller.reverse();
	}
	}

	void _handleHighlightChanged(bool value) {
	if (_pressed == value)
	return;
	setState(() {
	_pressed = value;
	if (value)
	_controller.forward();
	else
	_controller.reverse();
	});
	}

	@override
	void dispose() {
	_controller.dispose();
	super.dispose();
	}

	Color _getFillColor() {
	if (widget.highlightElevation == null \|\| widget.highlightElevation == 0.0)
	return Colors.transparent;
	final Color color = widget.color ?? Theme.of(context).canvasColor;
	final Tween<Color> colorTween = ColorTween(
	begin: color.withAlpha(0x00),
	end: color.withAlpha(0xFF),
	);
	return colorTween.evaluate(_fillAnimation);
	}

	BorderSide _getOutline() {
	if (widget.borderSide?.style == BorderStyle.none)
	return widget.borderSide;

	final Color specifiedColor = widget.enabled
	? (_pressed ? widget.highlightedBorderColor : null) ?? widget.borderSide?.color
	: widget.disabledBorderColor;

	final Color themeColor = Theme.of(context).colorScheme.onSurface.withOpacity(0.12);

	return BorderSide(
	color: specifiedColor ?? themeColor,
	width: widget.borderSide?.width ?? 1.0,
	);
	}

	double _getHighlightElevation() {
	if (widget.highlightElevation == null \|\| widget.highlightElevation == 0.0)
	return 0.0;
	return Tween<double>(
	begin: 0.0,
	end: widget.highlightElevation,
	).evaluate(_elevationAnimation);
	}

	@override
	Widget build(BuildContext context) {
	return AnimatedBuilder(
	animation: _controller,
	builder: (BuildContext context, Widget child) {
	return RaisedButton(
	textColor: widget.textColor,
	disabledTextColor: widget.disabledTextColor,
	color: _getFillColor(),
	splashColor: widget.splashColor,
	highlightColor: widget.highlightColor,
	disabledColor: Colors.transparent,
	onPressed: widget.onPressed,
	elevation: 0.0,
	disabledElevation: 0.0,
	highlightElevation: _getHighlightElevation(),
	onHighlightChanged: _handleHighlightChanged,
	padding: widget.padding,
	shape: _OutlineBorder(
	shape: widget.shape,
	side: _getOutline(),
	),
	clipBehavior: widget.clipBehavior,
	animationDuration: _kElevationDuration,
	child: widget.child,
	);
	},
	);
	}
	}

	// Render the button's outline border using using the OutlineButton's
	// border parameters and the button or buttonTheme's shape.
	class _OutlineBorder extends ShapeBorder {
	const _OutlineBorder({
	@required this.shape,
	@required this.side,
	}) : assert(shape != null),
	assert(side != null);

	final ShapeBorder shape;
	final BorderSide side;

	@override
	EdgeInsetsGeometry get dimensions {
	return EdgeInsets.all(side.width);
	}

	@override
	ShapeBorder scale(double t) {
	return _OutlineBorder(
	shape: shape.scale(t),
	side: side.scale(t),
	);
	}

	@override
	ShapeBorder lerpFrom(ShapeBorder a, double t) {
	assert(t != null);
	if (a is _OutlineBorder) {
	return _OutlineBorder(
	side: BorderSide.lerp(a.side, side, t),
	shape: ShapeBorder.lerp(a.shape, shape, t),
	);
	}
	return super.lerpFrom(a, t);
	}

	@override
	ShapeBorder lerpTo(ShapeBorder b, double t) {
	assert(t != null);
	if (b is _OutlineBorder) {
	return _OutlineBorder(
	side: BorderSide.lerp(side, b.side, t),
	shape: ShapeBorder.lerp(shape, b.shape, t),
	);
	}
	return super.lerpTo(b, t);
	}

	@override
	Path getInnerPath(Rect rect, { TextDirection textDirection }) {
	return shape.getInnerPath(rect.deflate(side.width), textDirection: textDirection);
	}

	@override
	Path getOuterPath(Rect rect, { TextDirection textDirection }) {
	return shape.getOuterPath(rect, textDirection: textDirection);
	}

	@override
	void paint(Canvas canvas, Rect rect, { TextDirection textDirection }) {
	switch (side.style) {
	case BorderStyle.none:
	break;
	case BorderStyle.solid:
	canvas.drawPath(shape.getOuterPath(rect, textDirection: textDirection), side.toPaint());
	}
	}

	@override
	bool operator ==(dynamic other) {
	if (identical(this, other))
	return true;
	if (runtimeType != other.runtimeType)
	return false;
	final _OutlineBorder typedOther = other;
	return side == typedOther.side && shape == typedOther.shape;
	}

	@override
	int get hashCode => hashValues(side, shape);
	}